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    <script>
        function identify() {
            return this.name.toUpperCase()
        }
        function speak() {
            let greeting = "Hello, I'm " + identify.call(this)
            console.log(greeting);
        }
        let me = {
            name: 'I am me'
        }
        let you = {
            name: 'I am you'
        }
        console.log(identify.call(me)); // I AM ME
        console.log(identify.call(you)); // I AM YOU
        speak.call(me) // Hello, I'm I AM ME
        speak.call(you) // Hello, I'm I AM YOU
    </script>
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